1. Field of the Invention
The present invention relates to a convertible multiple drill hitch for end wheel grain drills.
2. Prior Art
Combined working and transport hitches have been advanced with agricultural machinery in the past. For example. U.S. Pat. No. 4,171,022 illustrates a carrier which as shown appears to be a grain drill utilizing a separate wheeled cart to support the grain drill sections clear of the ground for transport. The plurality of grain drills which are positioned end to end for use, fold forwardly for transport, as shown in FIG. 1, and it appears that the apparatus is primarily designed for fully supporting press wheel grain drills for transport. The same disclosure is present in U.S. Pat. No. 4,214,637.
U.S. Pat. No. 3,548,954 shows a harrow cart that has outer sections folding rearwardly for transport position, and wheels 43 which engage the ground only when the harrow cart is rotated to its position holding the harrow sections out of the ground.
U.S. Pat. No. 3,791,673 shows an implement frame that folds so that the outer sections come forwardly up to the hitch pole, and the wheels of the outer sections are then lifted off the ground for transport.
U.S. Pat. No. 3,971,446 shows an agricultural implement towed by a tractor, with the outer sections of the implement swingable rearwardly for transport.
U.S. Pat. No. 4,157,735 shows a drill carrier that permits pulling the drills from one end upon lowering of wheels that are mounted alongside the front and rear of the machine. The front wheels are the ordinary caster wheels that are used with the drills, but the rear wheels have to be lowered onto the ground to lift the drills before towing. The idea of having wheels which engage the ground selectively for transport is thus disclosed therein.
U.S. Pat. No. 3,705,560 shows the general concept of having wheels which engage the ground for transporting agricultural implements.
U.S. Pat. No. 4,056,149 shows rearward pivoting of the outer sections of an agricultural implement for transporting. Hydraulic cylinders and linkages are operated to cause the outer sections to pivot about upright pivots shown at 24 in the drawings of that patent.
Additional patents uncovered in a preliminary search which are merely of general interest are U.S. Pat. Nos. 3,887,016; 3,986,464; 4,056,149; and 4,109,928. Each of these devices show various state of the art hitches for multiple section implements such as drills or the like.